Definition of Y in English:

Y

(also y)

noun

  • 1The twenty-fifth letter of the alphabet.

    • ‘Created by two of today’s wittiest, most imaginative minds, The Alphabet from A to Y with Bonus Letter Z! is a sheer delight from A to Z.’
    • ‘Find fun games, crafts, stories, and other educational activities all related to the letter Y.’
    1. 1.1Denoting the next after X in a set of items, categories, etc.
      • ‘After Boomers and X's, Here Come the Y's.’
      • ‘What Comes Next After Generation X? ... I would say, generation Y.’
    2. 1.2Denoting a second unknown or unspecified person or thing.
      ‘the claim that chemical X causes birth defect Y’
      • ‘Y denotes a second unknown or unspecified person or thing: the claim that chemical X causes birth defect Y.’
      • ‘In mathematics, Y is the second in a set of two or three unknowns comprising x, y, and z.’
    3. 1.3The second unknown quantity in an algebraic expression, usually the dependent variable.
      • ‘In algebra, a variable is a symbol used to represent any number. For example, in this equation:. 2(x+y) = 2x + 2y. x and y are variables.’
      • ‘By convention, we call the dependent variable y.’
    4. 1.4Denoting the secondary or vertical axis in a system of coordinates.
      [in combination] ‘the y-axis’
      • ‘Cartesian coordinate system with the circle of radius 2 centered at the origin marked in red. The equation of the circle is x2 + y2 = 4..’
      • ‘The horizontal axis is normally labeled x, and the vertical axis is normally labeled y.’
  • 2A shape like that of a capital Y.

    [in combination] ‘rows of tiny Y-shaped motifs’